CALAVERAS COUNTY (CBS13) – Crews were back searching a piece of property in Calaveras County in connection with the “Speed Freak Killers” case.

Sheriff’s deputies from both San Joaquin and Calaveras counties Thursday were once again searching a location off Leonard Road for remains of serial killers Wesley Shermantine and Loren Herzog.

The property being searched, once owned by the family of Shermantine, is where crews previously found the remains of victims Cyndi Vanderheiden and Chevy Wheeler.

Shermantine, one of the so-called “Speed Freak Killers,” is currently on death row in San Quentin for killing four people in a spree that lasted from 1984 to 1999. However, officials believe he and Herzog, who committed suicide earlier this year, are responsible for many more deaths.

Crews have also searched a well on some property in the San Joaquin County town of Linden. There they have found more than 1,000 bone fragments and other items.